
In the October 2014 Tip of the Month (TOTM), we demonstrated that Gas-Oil-Ratio (GOR) has a large impact on the capacity of crude oil gathering lines. In general as GOR increased the pressure drop increased which lowered the line capacity. In addition, at high pressures and low GOR, pressure drop was lower than the pressure drop for dead oil (solution gas is zero) because the viscosity of live oil is lower than viscosity of dead oil. This effect was bigger for the smaller line diameter. In this TOTM, we will study the impact of solution gas (Rs) on the crude oil properties in the gathering systems for one of the cases presented in the October 2014 TOTM. Specifically, the variation of the crude oil relative density and viscosity with the solution gas (Rs) will be studied. Finally, the impact of solution gas (Rs) on the oil and gas velocity and pressure drop along a gathering line for nominal pressure of 6900 kPag (1000 psig) and nominal pipe size of 101.6 mm (4 inches) will be demonstrated using multiphase rigorous method from a commercial simulator. The calculated properties, oil and gas velocities and pressure drops are presented in graphical format as a function of the oil stock tank volume flow rate and solution gas, Rs [Keep reading]